Specific challenge: In order to conduct close approach missions to NEOs, or to undertake mitigating demonstrations, it will be necessary to have a number of specific technologies and instruments readily available to conduct missions to asteroids with very weak gravitational fields.

In parallel, it is fundamental to acquire in-depth information on the internal structure and other physical properties of NEOs, not only for the design of most impact mitigation missions, but also for the assessment of the consequences of an impact on Earth.

Scope: In the first type of action, research is to be conducted on technologies and instruments relevant to orbiting, hovering, and manoeuvring close to small asteroids with very weak gravity fields. Accurate guidance, navigation and control (GNC) of a high-velocity (&gt; 10 km s-1) kinetic impactor spacecraft into a small NEO or for prolonged hovering around it, as well as orbit determination and monitoring (types of observation and precision) before, during, and after a mitigation attempt, require further technology development. The same applies to means for material sampling and collection, in-situ analysis and sample return to Earth, which are of relevance to physical characterisation.

In actions covering the second specific challenge, scientific research is needed to identify suitable objects for possible missions for detailed characterisation of properties and for developing demonstration and testing of deflection techniques. A characterisation of the NEO population, in particular the small NEOs (50 – 300 m) is to be undertaken. Typical mitigation-relevant physical properties of NEOs include sizes, albedos, mineralogy, shapes, densities, structures, porosities, frequency of binaries, frequency of rubble piles, etc.

The Commission considers that proposals requesting a contribution from the EU of between EUR 2 and 4 million would allow this specific challenge to be addressed appropriately. Nonetheless, this does not preclude submission and selection of proposals requesting other amounts.

Expected impact: For the first type of action, proposals are expected to contribute to the development of essential techniques and instruments, which would allow approaching and navigating in close vicinity and on the surface of asteroids and comets. The proposals should aim at TRL 5-6 (Technology Readiness Level[1]) and are expected to address technologies needed for deflection as well as for sample return missions.

Proposals addressing the second specific challenge are expected to lead to a comprehensive characterisation of NEO properties, which is mandatory for any mitigation or deflection mission. Data is to be made available in an open repository, taking into account complementary with existing databases. The identification of suitable targets and their accessibility for exploratory missions or mitigation demonstration missions is expected. An analysis of possible future actions in European programmes such as Horizon 2020 and ESA actions is expected.

Type of action: Research and innovation actions

[1] Technology Readiness Levels are defined in part G of the General Annexes. In the specific area of space, further details can be found in the European Space Agency website "Strategic Readiness Level - The ESA Science Technology Development Route". European Space Agency, Advanced Studies and Technology Preparation Division, http://sci.esa.int/sre-ft/50124-technology-readiness-level/05</p>